We're dividing 500621 by 42 
The aim is to understand the frequency of 42 in 500621.

Going ahead to step 1:
If we divide 5 by 42, we get 0 and a remainder of 5.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Fetch the next digit (0) from the dividend, attach it to 5 and continue: 50 / 42

Step 2:
When dividing 50 by 42, we get 1 with a remainder of 8.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we take 42 away from 50, we end up with 8.
Take the next digit (0) from the dividend and append it to 8, then repeat: 80 / 42

Let's proceed to step 3:
80 divided by 42 is 1 with a remainder of 38.
Record the quotient 1 as the next digit in the result. 
Result so far: 11.0
Deduct 42 from 80 and we're left with 38.
Bring next digit (6) of the dividend behind the 38 and repeat the process: 386 / 42

On to step 4:
42 goes into 386 9 times with a remainder of 8.
Put 9 as the next digit of the answer. 
Result so far: 119.0
The remainder is 8 after subtracting 378 from 386.
Include the next digit (2) from the dividend after 8, then repeat: 82 / 42

Let's proceed to step 5:
42 can be fit into 82 1 times, resulting in a remainder of 40.
The next digit of our result is 1. 
Result so far: 1191.0
Subtracting 42 from 82 leaves us with 40.
Include the next digit (1) from the dividend after 40, then repeat: 401 / 42

Step 6:
401 divided by 42 is 9 with a remainder of 23.
Put 9 as the next digit of the answer. 
Result so far: 11919.0
The remainder is 23 after subtracting 378 from 401.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Moving on to step 7:
If we divide 230 by 42, we get 5 and a remainder of 20.
The number 5 becomes the next digit in our result. 
Result so far: 11919.5
The remainder is 20 after subtracting 210 from 230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 8:
If we divide 200 by 42, we get 4 and a remainder of 32.
The number 4 becomes the next digit in our result. 
Result so far: 11919.54
Deduct 168 from 200 and we're left with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Moving on to step 9:
42 goes into 320 7 times with a remainder of 26.
The number 7 becomes the next digit in our result. 
Result so far: 11919.547
Subtract 294 from 320 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Step 10:
260 divided by 42 is 6 with a remainder of 8.
Record the quotient 6 as the next digit in the result. 
Result so far: 11919.5476
Subtract 252 from 260 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 11:
If we divide 80 by 42, we get 1 and a remainder of 38.
Record the quotient 1 as the next digit in the result. 
Result so far: 11919.54761
Subtract 42 from 80 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Going ahead to step 12:
380 divided by 42 is 9 with a remainder of 2.
Use 9 as the next digit of our solution. 
Result so far: 11919.547619
If we take 378 away from 380, we end up with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 13:
42 can be fit into 20 0 times, resulting in a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 11919.547619
Subtracting 0 from 20 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 14:
If we divide 200 by 42, we get 4 and a remainder of 32.
The number 4 becomes the next digit in our result. 
Result so far: 11919.54761904
Deduct 168 from 200 and we're left with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

After the division, we end up with 11919.54761904 and a remainder of 3.2e-08.